vmscan: get_scan_ratio() cleanup
KOSAKI Motohiro [Fri, 5 Mar 2010 21:41:47 +0000 (13:41 -0800)]
The get_scan_ratio() should have all scan-ratio related calculations.
Thus, this patch move some calculation into get_scan_ratio.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/vmscan.c

index 96ebe66..6278205 100644 (file)
@@ -1501,6 +1501,13 @@ static void get_scan_ratio(struct zone *zone, struct scan_control *sc,
        unsigned long ap, fp;
        struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc);
 
+       /* If we have no swap space, do not bother scanning anon pages. */
+       if (!sc->may_swap || (nr_swap_pages <= 0)) {
+               percent[0] = 0;
+               percent[1] = 100;
+               return;
+       }
+
        anon  = zone_nr_lru_pages(zone, sc, LRU_ACTIVE_ANON) +
                zone_nr_lru_pages(zone, sc, LRU_INACTIVE_ANON);
        file  = zone_nr_lru_pages(zone, sc, LRU_ACTIVE_FILE) +
@@ -1598,22 +1605,20 @@ static void shrink_zone(int priority, struct zone *zone,
        unsigned long nr_reclaimed = sc->nr_reclaimed;
        unsigned long nr_to_reclaim = sc->nr_to_reclaim;
        struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc);
-       int noswap = 0;
 
-       /* If we have no swap space, do not bother scanning anon pages. */
-       if (!sc->may_swap || (nr_swap_pages <= 0)) {
-               noswap = 1;
-               percent[0] = 0;
-               percent[1] = 100;
-       } else
-               get_scan_ratio(zone, sc, percent);
+       get_scan_ratio(zone, sc, percent);
 
        for_each_evictable_lru(l) {
                int file = is_file_lru(l);
                unsigned long scan;
 
+               if (percent[file] == 0) {
+                       nr[l] = 0;
+                       continue;
+               }
+
                scan = zone_nr_lru_pages(zone, sc, l);
-               if (priority || noswap) {
+               if (priority) {
                        scan >>= priority;
                        scan = (scan * percent[file]) / 100;
                }